CVE-2024-45258 is a critical-severity (CVSS 9.8) Improper Input Validation vulnerability in github.com/imroc/req/v3. A fix is available for github.com/imroc/req/v3 — see the affected versions and patch details below.
req may send an unintended request when a malformed URL is provided
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-45258.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-45258 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/imroc/req/v3🐹github.com/imroc/req🐹github.com/imroc/req/v2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
The req library is a widely used HTTP library in Go. However, it does not handle malformed URLs effectively. As a result, after parsing a malformed URL, the library may send HTTP requests to unexpected destinations, potentially leading to security vulnerabilities or unintended behavior in applications relying on this library for handling HTTP requests.
Despite developers potentially utilizing the net/url library to parse malformed URLs and implement blocklists to prevent HTTP requests to listed URLs, inconsistencies exist between how the net/url and req libraries parse URLs. These discrepancies can lead to the failure of defensive strategies, resulting in potential security threats such as Server-Side Request Forgery (SSRF) and Remote Code Execution (RCE).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/imroc/req/v3 | all versions | 3.43.4go get github.com/imroc/req/v3@v3.43.4 |
| 🐹Go | github.com/imroc/req | all versions | 3.43.4go get github.com/imroc/req@v3.43.4 |
| 🐹Go | github.com/imroc/req/v2 | all versions | 3.43.4go get github.com/imroc/req/v2@v3.43.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/imroc/req/v3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/imroc/req/v3 to 3.43.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-45258 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-45258 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-45258. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-45258 in your dependencies?
O3 Security finds CVE-2024-45258 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.